A water-bursting evaluation of the coal seam floor is critical to ensure safety of coal mine production. The vulnerability index method based on AHP is selected for this study’s evaluation method. Water pressure, measured specific yield, equivalent thickness of effective aquiclude, brittle rock thickness under mining pressure damage zone, distribution of faults, distribution of collapse column, distribution of endpoints, and the intersection of fault are taken as the evaluation index based on the analysis of geological data in the study area. The authors assessed the threat posed by the two aquifers in the lower portion of the coal seam. Separate evaluations were conducted on the Benxi and Ordovician limestone aquifers. The results’ veracity was confirmed by comparing the obtained results to the water bursting point and a few boreholes. The evaluation results provide recommendations for the safe operation of coal mines.

The purpose of this research was to understand the hydrogeochemical characteristics and assess the quality of phreatic and confined groundwater in southern Hebei Province. A total of 107 groundwater samples were collected, representing different aquifer conditions over the study area. Multivariate statistical analysis, hydrochemical maps, ionic ratio coefficients, geographic information system (GIS) and geochemical simulation were comprehensively and systematically used to reveal the hydrochemical characteristics of groundwater and its controlling mechanism. The results revealed that both phreatic (pH = 7.02–9.08) and confined groundwater (pH = 7.00–10.60) were slightly alkaline. The hydrochemical types were mainly present as the HCO₃-Ca-Mg type in the western premontane area and mixed Ca-Mg-SO₄-Cl and Na-Cl-SO₄ types in the eastern plains. The hydrochemical composition was dominated by water–rock interactions of natural processes, including silicate weathering, dissolution of sulfate minerals (gypsum, anhydrite), and cation-exchange adsorption. Anthropogenic activities were the main factor causing NO₃⁻ content in some groundwater samples to exceed the geochemical baseline. The hydrogeochemistry of groundwater in different aquifers was significantly varied. The average contents of TH, TDS, Na⁺, Ca²⁺, Mg²⁺, Cl⁻ and SO₄²⁻ in phreatic aquifers were significantly higher than those in confined aquifers. The Entropy Weighted Water Quality Index (EWQI) results revealed that 17.78% of phreatic and 50% of confined water samples were meeting the purpose of drinking water. The groundwater samples with EWQI values exceeding 100 were mainly situated in the Handan urban area and the eastern region of Xingtai City, which should be avoided for direct utilization and needs to be improved through protection and management measures, to enhance the quality of groundwater. Correlation analysis showed that groundwater quality was significantly dominated by TH, TDS, Na⁺, Mg²⁺, Cl⁻ and SO₄²⁻ concentrations.

To obtain the evaluation results that are more in line with the water-richness of thin limestone aquifers for ensuring the safety of coal mine production, dewatering test and hydrochemical analysis were conducted on Benxi thin limestone aquifer to explore and quantify the hydraulic connection between the Ordovician limestone aquifer and the thin limestone aquifer in Benxi formation. Based on the characteristics of water-bearing media, such as aquifer thickness, core recovery, flushing fluid consumption and permeability coefficient, the CRITIC weighting method was used to determine the weight of each factor’s influence on the water-richness of thin limestone aquifers, so as to establish the model for evaluating the water-richness of thin limestone aquifer in Benxi formation, and draw the thematic map of the main controlling factors of the aquifers. Then, the information was normalized and superimposed using the multi-source information fusion technology, thereby obtaining the zoning of the aquifer per different water-richness. The evaluation results show that the thin limestone aquifer in Benxi formation can be divided into five areas, i.e. “strong, relatively strong, medium weak, relatively weak and weak ” areas. With a stronger hydraulic connection with the Ordovician limestone aquifer, the northwest part of the research area has a greater water-richness than the southeast part, which was verified by the pumping test carried out in the study area.

In order to ensure the safe production of Gequan coal mine, it is important to carry out a water bursting evaluation of the coal seam floor. This study selects vulnerability index method based on AHP as the evaluation method. Based on the analysis of the geological data in study area, water pressure, measured specific yield, equivalent thickness of effective aquiclude, brittle rock thickness under mining pressure damage zone, distribution of faults, distribution of collapse column, distribution of endpoints and intersection of fault and fault-scale index are taken as the evaluation index. As there are two aquifers in the lower part of the coal seam that are a threat to mining, the author evaluated Benxi limestone aquifer and Ordovician limestone aquifer separately, the reliability of the results was verified by comparing the results obtained with the water bursting point and some of the boreholes. The results of the evaluation provide guidance on the safe production of coal mines.

Accurate prediction of aquifer water abundance is critical for coal mine safety, yet traditional static models often fail to capture the spatial heterogeneity and non-stationarity of hydrogeological conditions. This study proposes a dynamic evaluation methodology integrating Grey Relational Analysis, the Analytic Hierarchy Process, and a Time-Varying Parameter Cubature Kalman Filter (TVP-CKF). By reconceptualizing spatial borehole data as a dynamic time-series process, the model recursively updates the contribution weights of six controlling factors based on monitoring data from 2012 to 2020. Analysis reveals a structural shift in the groundwater system: the influence of hydrochemical factors (TDS) has diminished, while hydraulic conductivity has become the dominant control over time. The TVP-CKF model significantly outperformed static regression and recursive least squares baselines, demonstrating superior convergence stability and precisely capturing transient inflow fluctuations. Furthermore, its uncertainty quantification effectively bounded extreme low-flow events within 95% confidence intervals. This approach validates the necessity of adaptive modeling in evolving geological environments, providing a robust, risk-quantified tool for precise water inrush prevention.